In construction, and other applications, it is often important to know the vertical displacement between two selected and spaced locations. Typically, such vertical displacements are determined by the use of a tripod, surveyor's level, and rod which are used in a conventional manner to detect vertical displacements between a reference point and selected and spaced location. Measurements of this type are labor intensive operations. Further, it is not uncommon for inaccurate measurements to be taken, especially if the laborer is insufficiently trained.
Numerous liquid leveling systems have been developed in the past. Known prior art is illustrated in the following U.S. Pat. Nos.:
______________________________________ PATENT NO. INVENTOR ISSUE DATE ______________________________________ 386,924 A. Kegel July 31, 1888 451,680 A. Gamble May 5, 1891 547,864 Sherman October, 1895 915,084 R. Eberhard March 16, 1909 965,659 J. L. Russell July 26, 1910 1,012,993 J. H. Dissett December 26, 1911 1,042,248 W. N. McGowan October 22, 1912 1,231,162 I. Husby June 26, 1917 2,532,883 P. L. Bennett, et al. December 5, 1950 3,015,167 J. M. Chapman January 2, 1962 3,132,428 H. O. Haissig, et al. January 12, 1962 3,137,091 N. Clare, et al. June 16, 1964 3,144,234 K. Artmann August 11, 1964 3,310,880 A. W. Watts March 28, 1967 3,680,216 L. W. Hallanger August 1, 1972 3,768,766 A. O. Bain October 30, 1973 3,910,576 X. Leonhart October 7, 1975 ______________________________________
While these leveling systems, as a general rule, incorporate one or more liquid containing members, the systems generally are designed to provide a representation of whether two points are level, one with respect to the other.
Contrawise, the present invention includes as an object, a feature to measure the vertical displacement between selected and spaced locations.
It is another object of the present invention to provide a system for making vertical measurements which would normally be made by a builder's level, rod and tripod, and to enable making such measurement readily and accurately determinable by a single worker.
Another object of the present invention is to provide such a measuring system which can be readily manufactured and easily maintained, and which is readily portable.